The invention, in one of its aspects, pertains to automatic hair and scalp treatment machines. In another of its aspects the invention pertains to improvements in the apparatus characterized in earlier U.S. Pat. No. 4,834,121.
The invention which was the basis of U.S. Pat. No. 4,834,121 overcame the problems associated with U.S. Pat. No. 3,521,647, and particulary the disadvantages of scalp massaging devices, such as those described in U.S. Pat. Nos. 2,566,600, 2,854,970 and 3,177,868. The invention in 3,521,647 did have some drawbacks. It was not until after a large number of hair treatments that it was found that in the earlier machine the contacting action was not quite that desired. Accordingly it was then improved by the invention in U.S. Pat. No. 4,834,121. That apparatus included a bowl, and a closure therefor, adapted to enclose the head with the face outside the closure. Also included were spray manifolds on an oscillating arcuate header, and driving means imparting partial rotation to the arcuate header. It was found that there were gaps or skips in spray in prior art devices. It was this imperfect action which was improved by the invention in U.S. Pat. No. 4,834,121. In U.S. Pat. No. 4,834,121, means were provided of dispensing treating solutions in the form of sprays so oriented that they coacted with each other as they sprayed the head from front to back.
The apparatus of U.S. Pat. No. 4,834,121 solved most of the problems which previously surfaced. But one unsolved problem was that of contacting the area of the head behind the ears. If hair is being shampooed, this area is relatively unimportant. Hence attention has not been accorded that aspect of the treating apparatus. Rather, to avoid getting solutions in the ears, no attempt has been made to direct sprays close to them. The spreding of the sprays has been relied upon to treat the space around the ears. However, with the discovery that sprays can be used in the treatment of dermatoses such as psoriasis, it has become much more important to contact the head behind the ears. To do so was not without its problems, primarily because the curve or path which the spray must travel about the ears is a cardioid. It has now been found that under certain conditions spray from nozzles on an oscillating manifold can be made to trace such a curve around the ears.